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Unread 10-31-2013, 04:28 PM   #91
laybackman
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Quote:
Originally Posted by flipit View Post
and from a mustang forum in a place,
a member said
"If memory serves me correcly, the green connector goes off to the fuel pump relay."
not that that is really important at the moment, but it's an answer, and might help with the future clean up
It is important because the Ford product this harness and ECU you have in your YJ used a fuel pump relay originally. It was controlled by the ignition circuit.

I think the answer lies in that terminal board which seems to be the major point (possibly not the only point) where Mustang wiring meets YJ wiring.

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Unread 10-31-2013, 04:41 PM   #92
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Quote:
Originally Posted by laybackman View Post
It is important because the Ford product this harness and ECU you have in your YJ used a fuel pump relay originally. It was controlled by the ignition circuit.

I think the answer lies in that terminal board which seems to be the major point (possibly not the only point) where Mustang wiring meets YJ wiring.
The wiring specific to the fuel pump is good up to and past the terminal board, but yes that will be a large point of fixing once i get there. along with the pdc, and the wiring harness connectors, as some of those have been recreated.
I'd show you the entire mess and all the problems and points, but that could take hours.
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Unread 10-31-2013, 05:26 PM   #93
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If you wanted to get this running you could wire in that relay with 4 wires and have it controlled through a relay by the ECU the way it should be.
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Unread 10-31-2013, 06:08 PM   #94
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Quote:
Originally Posted by flipit View Post
I did,
this afternoon I pretty much traced all the wires, because when I bought the fuel pump, it was new, so I plugged it in, and didn't have the chance to really test it til now, and of course the gas isn't pumping.
the ground grounds, the hot is hot, and the gauge wire goes to the gauge, It was off by 1/4 tank before the problem, but I'm sure it still functions quite properly.
my real hang up was the sending unit.
right before the sending unit is a "connector" (temrinal, plug something, insert correct nomenclature here) so I unhooked it and checked the three incoming wires. once those were all verified, I checked the ground to it's welded spot on top of the fuel sending unit, and that point, along with pretty much the whole unit, is properly grounded.
This is where it got tough for me, and my far from advanced knowledge.
on top of the underneath of the sending unit, there are two prongs, hot, and gauge. starting at the hot prong, the electrical circuit as I noted, is as follows-
Hot prong~left pump bolt^right pump bolt~sending unit ground point.
(~ is a small clip on wire, and the ^ is like, one is the positive bolt, one is negative, hope that makes sense)
attached to the sending unit ground point is the fuel level gauge, which has a wire coming off of it, going to the gauge prong on top.
so, when I plugged the hot wire into the hot prong, the circuit was completed.
for both-(i thought)
so i thought the gauge was pulling too much voltage, sending the pump down to only 1.6 volts (1.9 with good contact)
I'm kinda new to electrical, I've always enjoyed the mechanical aspect much more,
So,
closer to the evening I finally realized it wasn't the same circuit,
it's some kind of weird thing that i can only presume makes sense in the electrical world.
so i pulled off the fuel pump,
took the two cables, put one on the batterys ground terminal,
and one on the positive terminal.
and there was no pumping sound,
no smoke cloud-
nothing...
so i think either i bought a faulty pump,
or way more likely, I broke it along the way.
so I'll be picking a new one up Tuesday.
I dunno, maybe Monday If I have the time.
and we'll see if a new one fixes all my problems.
Going way back into your thread. Did you get another fuel pump? Is it a stock Jeep fuel pump? Are you going to plug it into the stock fuel pump plug shown in one of your pictures?

Did you ever hot wire this new pump using two jumper wires?

We are throwing a bunch of stuff at you but this car ran the way it was even if it has dangerous/poopy wiring.
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Unread 10-31-2013, 06:09 PM   #95
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Quote:
Originally Posted by Que89YJ View Post
If you wanted to get this running you could wire in that relay with 4 wires and have it controlled through a relay by the ECU the way it should be.
very true.
The problem there is-
that's a quick fix.
There is a lot of dangerous wiring in this rig,
and as I know you are well aware,
that could come with some very negative repercussions.

I have a hot wire that isn't supposed to be hot-
well i haven't started the car since that wire became hot.
what else is hot?
I can't just leave a loose hot wire,
that's just begging for more problems.

I'd love to get this engine fired up,
but even so,
this jeep won't leave the garage before 2014.
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Unread 10-31-2013, 06:14 PM   #96
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Quote:
Originally Posted by laybackman View Post
Going way back into your thread. Did you get another fuel pump? Is it a stock Jeep fuel pump? Are you going to plug it into the stock fuel pump plug shown in one of your pictures?

Did you ever hot wire this new pump using two jumper wires?

We are throwing a bunch of stuff at you but this car ran the way it was even if it has dangerous/poopy wiring.
a third fuel pump?
no

the first was a bosch,
the second I'm not sure the brand,
the fuel sending unit is stock,
the fuel pump itself is, i mean,
you know, i bought the second one asking for a fuel pump for a 93 wrangler,
so it's not custom or anything, you could put it in your yj-
I'm going to install the third right back into the sending unit just like the first two, but not until I can control it.
I have to but the fuel pump and battery as both are shot,
I'm borrowing my brothers battery currently.

I put two wires on the pump and put both wires to the battery, if that's what you are refering to?
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Unread 10-31-2013, 06:28 PM   #97
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Quote:
Originally Posted by flipit View Post
a third fuel pump?
no

the first was a bosch,
the second I'm not sure the brand,
the fuel sending unit is stock,
the fuel pump itself is, i mean,
you know, i bought the second one asking for a fuel pump for a 93 wrangler,
so it's not custom or anything, you could put it in your yj-
I'm going to install the third right back into the sending unit just like the first two, but not until I can control it.
I have to but the fuel pump and battery as both are shot,
I'm borrowing my brothers battery currently.

I put two wires on the pump and put both wires to the battery, if that's what you are refering to?
"I put two wires on the pump and put both wires to the battery, if that's what you are refering to?"

Yes. One wire to + battery post and one wire to - battery post....I hope!

This YJ ran just the was it was, correct?. Got to get what you know is a good fuel pump in it. That essentially is starting from point A.....more or less...
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Unread 10-31-2013, 06:40 PM   #98
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Quote:
Originally Posted by laybackman View Post
"I put two wires on the pump and put both wires to the battery, if that's what you are refering to?"

Yes. One wire to + battery post and one wire to - battery post....I hope!

This YJ ran just the was it was, correct?. Got to get what you know is a good fuel pump in it. That essentially is starting from point A.....more or less...
one to each post? aww crap....
I'm joking, but yes,
welcome to starting point t, more or less :P

The YJ ran with pump A.
pump a shredded,
so starting point a, replace pump, check!
reinstall everything, Check!
start vehicle- (wait, ill be back in a few years...)
OKAy! and...batteries dead, hold on,
trickle charges it...
wait! battery is fried,
steals brothers,
wait,
new pump is fried!
contacts JF community,
wait,
why is the wire hot!!!???
I can't put a working fuel pump into the jeep,
because I am not keen on burning another $70 part.
but i might have some good news in an hour,
when i get to the house.
gotta feed the animals,
then I'm going to check the first pump again,
rumor has it that it still spins...
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Unread 11-01-2013, 09:06 AM   #99
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Quote:
Originally Posted by flipit View Post
one to each post? aww crap....
I'm joking, but yes,
welcome to starting point t, more or less :P

The YJ ran with pump A.
pump a shredded,
so starting point a, replace pump, check!
reinstall everything, Check!
start vehicle- (wait, ill be back in a few years...)
OKAy! and...batteries dead, hold on,
trickle charges it...
wait! battery is fried,
steals brothers,
wait,
new pump is fried!
contacts JF community,
wait,
why is the wire hot!!!???
I can't put a working fuel pump into the jeep,
because I am not keen on burning another $70 part.
but i might have some good news in an hour,
when i get to the house.
gotta feed the animals,
then I'm going to check the first pump again,
rumor has it that it still spins...
My son owns a 1993 Mustang and has an FSM for it. We need to know what some of the pin outs on your Ford ECU are for.

Questions: Does your Ford engine harness have a power distribution center on it with fuses/relays?
Does it have any relay on it dangling off of the harness itself?
How much of the YJ harness is left under the hood?
Is the YJ PDC still there?
Does any of the Mustang wiring go there?
Was this YJ that torn apart inside when it last ran?

You are our eyes on this one so expect some odd questions.
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Unread 11-01-2013, 09:23 AM   #100
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Quote:
Originally Posted by laybackman View Post
My son owns a 1993 Mustang and has an FSM for it. We need to know what some of the pin outs on your Ford ECU are for.

Questions: Does your Ford engine harness have a power distribution center on it with fuses/relays? the only PDC is the YJ PDC
Does it have any relay on it dangling off of the harness itself? not that i could see, the only relays/fuses i know of are the PDC and the fuse bx under the steeering wheel
How much of the YJ harness is left under the hood? I'm not sure. It's so mangled I can't tell, if i had to guess I would say the whole thing is still there, there is a plentiful amount of wires just dangling in the compartment.
Is the YJ PDC still there? yes
Does any of the Mustang wiring go there?the stock YJ wires go in, along with two red wires, one to the starter, and one to the ASD
Was this YJ that torn apart inside when it last ran?no, haha, ummm... if i wanted to put it back together, I would install the stock dashboard(just the metal flat section) and connect all the dash connectors, then re-wiretie all the loose wires and reconnect the air conditioning cables. then put in the seats and the roll cage. and tighten the steering wheel screws.

You are our eyes on this one so expect some odd questions.
If you need eyes on anything, I can point and shoot.
but trust me,
similar questions have gone between my father and I, when we first ran the stereo.

one thing i will say, there are some interesting connectors coming off the harness, quite decent in size, you could fit a fuse in there but i don't think it is designed to have one?
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Unread 11-01-2013, 09:40 AM   #101
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Quote:
Originally Posted by flipit View Post
If you need eyes on anything, I can point and shoot.
but trust me,
similar questions have gone between my father and I, when we first ran the stereo.

one thing i will say, there are some interesting connectors coming off the harness, quite decent in size, you could fit a fuse in there but i don't think it is designed to have one?
There are fuses that go into small connectors BUT if you did not remove any don't add any. ANY change made may add to the problem you have.

The only changes made was in the interior. I wonder if that is where the problem is? That is where I would concentrate my detective work.

Check for a ground that is screwed into the body near the emergency brake bracket. That one is wicked important.

The battery died, but if left on a bench by itself, it would do that anyway in time.
Got to go for now, but I'll check in again ASAP.
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Unread 11-01-2013, 10:26 AM   #102
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Going by the diagram LBM posted sinse the wiring colors seem to match, you have 4 power lines, none of which you have located a fuse for. These are the circuits that need to be wired in to make it run and IMO the 4 that need to be rewired.

Fuel pump pink/black
PCM power relay Yellow
O2 sensors Grey Yellow
Ign coil Red/Lt Green

You are missing 2 key relays
1) Fuel pump
2) Pcm power

And you currently have a constant power from some unknown circuit powering back through to feed the fuel pump.
Add on top of this you have a terminal strip just screwed into the bulkhead with live power.

You are fighting hard to trace down 1 circuit but look at the big picture here. Even if you got the fuel pump taken care of I would not drive this jeep around the block until you get the other stuff taken care of but its your call. I had you look over on the bulkhead connector and the ignition switch to try and chase down which circuits are wired into those 4. Did you narrow it down? You are going to have to keep pulling circuit to figure out which one he tapped into to wire it up. If it is unfused it wouldnt surprise me at this point!
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Unread 11-01-2013, 10:48 AM   #103
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Quote:
Originally Posted by Que89YJ View Post
Going by the diagram LBM posted sinse the wiring colors seem to match, you have 4 power lines, none of which you have located a fuse for. These are the circuits that need to be wired in to make it run and IMO the 4 that need to be rewired.

Fuel pump pink/black
PCM power relay Yellow
O2 sensors Grey Yellow
Ign coil Red/Lt Green

You are missing 2 key relays
1) Fuel pump
2) Pcm power

And you currently have a constant power from some unknown circuit powering back through to feed the fuel pump.
Add on top of this you have a terminal strip just screwed into the bulkhead with live power.

You are fighting hard to trace down 1 circuit but look at the big picture here. Even if you got the fuel pump taken care of I would not drive this jeep around the block until you get the other stuff taken care of but its your call. I had you look over on the bulkhead connector and the ignition switch to try and chase down which circuits are wired into those 4. Did you narrow it down? You are going to have to keep pulling circuit to figure out which one he tapped into to wire it up. If it is unfused it wouldnt surprise me at this point!
I agree with you Que, BUT this supposedly ran at one time. Then he went away then it wouldn't start when he came back.

Then he tore out the interior. Change can cause problems. Flipit tore out the interior. IF this YJ ran at one time and he could get it running again would be nice just to see what the PO did. Then this YJ needs a whole rewire....FOR SURE!!

What is left of the YJ harness? How much of the Mustang wiring is there? (relays seem to be removed OR bypassed) was used are the two $64,000.00 questions.
I need to know what the wiring in the Mustang ECU does.
Looking at any wiring schematic power always come from the top when possible.

On the stock Mustang wiring diagram, the wiring for the fuel pump constant power to the relay for the fuel pump is the PNK/BLK wire which is a fusible link. Power to the PCM and then the Fuel pump relay is the Yel wire that also has a fusible link. That makes sense. RD wire.

The Lt BLU ORG wire has to be ground. That closes the PC relay allowing voltage to flow through the PCM relay via the RD wire and close fuel pump relay allowing the both relays to close and and allows power to go through the FP relay to the fuel pump...or I am completely stumped! Maybe I better hit the bottle of jameisons
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Unread 11-01-2013, 12:11 PM   #104
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Jamesons

Yeah, I had him hook his meter up to the fuel pump circuit so he could see the 12 volts and start pulling the circuits like the ignition switch and the bulkhead connector to see if we could narrow the circuit down. Fuses were next if the bulhead worked.
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Unread 11-01-2013, 12:54 PM   #105
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Originally Posted by laybackman View Post
There are fuses that go into small connectors BUT if you did not remove any don't add any. ANY change made may add to the problem you have.

The only changes made was in the interior. I wonder if that is where the problem is? That is where I would concentrate my detective work.

Check for a ground that is screwed into the body near the emergency brake bracket. That one is wicked important.

The battery died, but if left on a bench by itself, it would do that anyway in time.
Got to go for now, but I'll check in again ASAP.
The interior is fine. I mean, something might have happened there, but all i did was remove the dash panel. I can put it back on again if that will make you more comfortable.

I'll check for the ground sometime tonight if I can, I have quite a bit going on today.

Again, right now my assumptions are close to the ignition, gotta find out where that hot is coming from. I'll bring back something informational tonight- like, 6-9 west coast time.
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